On 2011-05-16 14:16, Guilhem Bichot wrote:
> Tor Didriksen a écrit, Le 16.05.2011 13:48:
>> #At file:///export/home/didrik/repo/trunk-dynarray/ based on
>> revid:andrei.elkin@stripped
>>
>> 3088 Tor Didriksen 2011-05-16
>> Bug#12552221 - MEMORY LEAK IN UPDATE_REF_AND_KEYS
>> Allocate array in memroot rather than heap.
>> Fixes the leak, and also yields a 1-2% performance gain with
>> sysbench if you have lots of cpus/threads.
>> @ sql/mem_root_array.h
>> A typesafe replacement for DYNAMIC_ARRAY.
>> We use MEM_ROOT for allocating storage, rather than the C++
>> heap.
>> The interface is chosen to be similar to std::vector.
>
> This existing template in sql_array.h looks to have similarities with
> the above new one:
>
> /*
> Array of pointers to Elem that uses memory from MEM_ROOT
>
> MEM_ROOT has no realloc() so this is supposed to be used for cases when
> reallocations are rare.
> */
>
> template <class Elem> class Array
> {
> enum {alloc_increment = 16};
> Elem **buffer;
> uint n_elements, max_element;
> public:
> Array(MEM_ROOT *mem_root, uint prealloc=16)
> ...
>
> Maybe you can reuse/modify it...
> If not, maybe it can be deleted and your new stuff can be used
> instead... Having two "dynamically growing arrays allocating in
> MEM_ROOT" sounds like redundancy...?
Yes, I know.
But Array works on pointers only, rather than objects.
I am all for removing it, and using my new class instead.
-- didrik
